1. Field of the Invention
The present invention relates to a stereoscopic optical device and a method of making the same, and more particularly, to a stereoscopic optical device with an alignment film, which has an identical aligning direction of fast axis for liquid crystal molecules in different regions, an identical aligning direction of slow axis for liquid crystal molecules in different regions, and different pre-tilt effects on liquid crystal molecules in different regions, and a method of making a stereoscopic optical device without using patterned masks to make different regions of the alignment film characterized with different pre-tilt effect on liquid crystal molecules.
2. Description of the Prior Art
The principle of the stereoscopic display technology includes respectively delivering different images to a left eye and a right eye of a viewer, making the viewer feeling the gradation and the depth of the images, and generating the stereoscopic effect by analyzing and overlapping images separately received by the left eye and the right eye in the cerebrum of the viewer.
Please refer to FIG. 1. FIG. 1 is a schematic diagram illustrating a conventional stereoscopic optical device. As shown in FIG. 1, the conventional stereoscopic optical device 10 includes a substrate 12, an alignment film 14 disposed on the substrate 12, a quarter wavelength phase retardation film 16 disposed on the alignment film 14, and a patterned phase retardation film 18 disposed on the phase retardation film 16. The quarter wavelength phase retardation film 16 and the patterned phase retardation film 18 are respectively a liquid crystal layer, and the patterned phase retardation film 18 includes a plurality of alternately arranged first regions 181 and second regions 182. The first region 181 has a half wavelength phase retardation effect, and the second region 182 does not have phase retardation effects.
The stereoscopic optical device 10 is disposed on a display surface of a display panel, such as a liquid crystal display panel 20. After passing through the stereoscopic optical device 10, the linear polarized light generated from a polarizer 22 above the liquid crystal display panel 20 may pass through the first region 181 of the patterned phase retardation film 18 and the second region 182 of the patterned phase retardation film 18 and become different circularly polarized lights, such as left-hand circular polarized light and right-hand circular polarized light. According to the different circular polarized light, the left eye and the right eye of the viewer wearing polarized glasses may receive different images and the stereoscopic effect may then be generated.
However, in the conventional stereoscopic optical device 10, two pieces of phase retardation films, which are the quarter wavelength phase retardation film 16 and the patterned phase retardation film 18, have to be employed, and that may lead to thicker stereoscopic optical devices, higher cost, and worse optical properties. Besides, the cost and the complexity of the manufacturing process may be further increased, because masks have to be employed to define patterns of the patterned phase retardation film 18.